Balloon catheters with increased column strength

ABSTRACT

An intravascular balloon catheter that may include, for example, a first elongate member having a proximal end, an opening at the distal end and a lumen therebetween, a balloon defining a cavity, the balloon having a proximal waist sealingly attached to the first elongate member proximal the distal end, a distal waist, and a tubular portion therebetween, a second elongate member having a proximal end, a distal end and a lumen therebetween, the second elongate member disposed in the first elongate member and sealingly attached to the balloon distal waist, and a stopper attached to the second elongate member and disposed in the balloon cavity distal the distal end of the first elongate member, the stopper having an outer profile that prevents movement of the first elongate member thereover the first elongate member having an inner diameter at the distal end large enough to permit the passage of fluid therethrough over the second elongate member.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/148,726, filed Jun. 9, 2005, now U.S. Pat. No. 9,352,133.

FIELD OF THE INVENTION

The invention pertains to balloon catheters such as angioplasty orstent-delivery catheters and more particularly to coaxial embodimentshaving a guidewire lumen therethrough.

SUMMARY

One embodiment pertains to an intravascular balloon catheter havinginner and outer catheter tubes with a a stopper attached to the innertube and disposed in the balloon cavity distal the distal end of theouter tube, the stopper having an outer profile that prevents movementof the outer tube thereover while permiting flow of inflation fluid tothe balloon cavity. The catheter may include one or more orifices in theouter tube proximal the first elongate member distal end and distal theballoon proximal waist. The stopper may include two or more lobes thatdefine gaps therebetween to allow fluid passage from the distal end ofthe first elongate member into the balloon cavity. Alternatively, thestopper may be a basket attached to the second elongate member andflaring proximally to define a cavity sized to receive the distal end ofthe first elongate member or a cap attached to the second elongatemember and flaring proximally to define a cavity sized to receive thedistal end of the first elongate member that may have one or moreorifices in a side wall thereof. The stopper may be fixed to the outertube and may have a proximal face sized to abut a distal face of theouter tube and prevent distal passage of the outer tube thereover.Alternatively, the inner tube may have a first outer diameter and asecond larger outer diameter distal the first outer diameter, the secondouter diameter proximal end disposed in the balloon cavity and sized toprevent passage of the outer tube thereover and there may be a taper ora step-wise transition between the first outer diameter and the secondouter diameter. The proximal waist of the catheter may extend distallyof the distal end of the outer tube and the stopper may be fixed to theinner and sized to abut a distal face of the outer tube and may have oneor more or openings positioned to allow the passage of fluid from aproximal to a distal side thereof. The catheter may include a radiopaquemarker having a profile, the radiopaque marker being fixed to the outertube and disposed in the balloon cavity, wherein the stopper is slidableon the second elongate member and is disposed between a distal face ofthe outer tube and the radiopaque marker, the stopper having a proximalface sized to abut the distal face of the outer tube and prevent distalpassage of the outer tube thereover and a distal face sized to abut theradiopaque marker and sized to prevent distal passage of the stopperover the radiopaque marker.

Another embodiment pertains to a balloon catheter having a a wireattached to the outer tube proximate the proximal end thereof andattached to the inner tube in the general area of the balloon. The wiremay include a coil disposed around the inner tube proximal the distalattachment point, one or more attachment points between the wire and theinner tube proximal the distal attachment point, or a radiopaque markerattached to the inner tube and disposed in the balloon cavity, whereinthe wire is attached to the inner tube at the radiopaque marker.

Another embodiment pertains to a balloon catheter having a coil slidablydisposed about the inner tube in the balloon cavity, the coil attachedproximally to the proximal balloon waist or the distal end of the outertube and attached distally to the distal balloon waist. The coil mayalso be attached distally to the inner tube proximate the distal balloonwaist.

Another embodiment pertains to a balloon catheter wherein the stopper isattached to both the outer and inner tube, and the stopper permits afirst relative position between the outer and inner tube where thestopper has a first length and second relative position between theouter and inner tube where the stopper has a second length shorter thanthe first length, the stopper permitting fluid flow therethrough. Thestopper may include a plurality of telescoping wire rings or a pluralityof sliding segments connected to each other seriatim.

Another embodiment pertains to a balloon catheter where the ballooninner surface has a first texture thereon, the second elongate memberouter surface has a second texture thereon, where the first and secondtextures interact when the balloon is deflated to prevent relativemovement of the balloon and the inner tube. The first texture mayinclude a plurality of bumps and the second texture may include aplurality of transverse ribs or zigzag ribs. In an alternativeembodiment, the balloon inner surface and the second elongate memberouter surface have a tacky adhesive thereon that prevents relativemovement of the balloon and the second elongate member in the deflatedcondition

Another embodiment pertains to a balloon catheter where an interferencefit proximate the distal waist of the balloon prevents relative movementbetween the first and second elongate members. The outer surface of theinner tube may have an irregular profile that provides the inteferencefit with the inner surface of the first elongate member, where the firstelongate member outer surface and the second elongate member innersurface defining one or more fluid passageways that fluidly connect theballoon cavity to the proximal end of the catheter. For example theinner tube may have a hexagonal profile. The outer tube may have areduced inner diameter proximate the balloon proximal waist.

In an alternative embodiment, the catheter may include an insert betweenthe first and second elongate members proximate the balloon proximalwaist, the insert providing the interference fit and providing fluidpassage lumens to fluidly connect the balloon cavity and the catheterproximal end. The insert may have circular inner profile and anon-circular outer profile such as a polygonal or an elliptical outerprofile. Alternatively the insert may have a circular outer profile, aproximal face, a distal face and one or more lumens therebetween.

Another embodiment pertains to a balloon catheter that includes at leastone protrusion extending inward from the inner surface of the outer tubeand at least one protrusion separate from the protrusion from the outertube extending outward from the outer surface of the inner tube, theprotrusions cooperatively engaged to prevent relative axial movementbetween the outer and inner tube. The protrusion from the outer tube maydefine a ring-shaped groove and wherein the at least one protrusion fromthe inner tube comprises one or more tabs which fit in the groove, theprotrusions providing one or more gaps therebetween for fluid flow. Theprotrusion from the first elongate member may taper proximally anddistally. The protrusion from the second elongate member may be a ringand wherein the at least one protrusions from the outer tube may be tabsbetween which the ring is confined. The tabs may be axially aligned. Theat least one protrusion in the outer tube may be formed by indenting thewall thereof. The at least one protrusion in the inner tube may includea proximal ring and a distal ring. The proximal ring may taperproximally and the distal ring taper may taper distally.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more completely understood in consideration of thefollowing detailed description of various embodiments of the inventionin connection with the accompanying drawings in which:

FIG. 1 is a partial diagrammatic view of a balloon catheter.

FIG. 2 is a partial diagrammatic view of a balloon catheter.

FIG. 3 is a partial diagrammatic view of a balloon catheter.

FIG. 4 is a partial diagrammatic view of a balloon catheter.

FIG. 5 is a partial diagrammatic view of a balloon catheter.

FIG. 6 is a partial diagrammatic view of a balloon catheter.

FIG. 7 is a partial cross-sectional view of the balloon catheter of FIG.6.

FIG. 8 is a partial cross-sectional view of a balloon catheter.

FIG. 9 is a partial cross-sectional view of a balloon catheter.

FIG. 10 is a partial cross-sectional view of a balloon catheter.

FIG. 11 is a partial cross-sectional view of a balloon catheter.

FIG. 12 is a partial cross-sectional view of a balloon catheter.

FIG. 13 is a partial cross-sectional view of a balloon catheter.

FIG. 14 is a partial cross-sectional view of a balloon catheter.

FIG. 15 is a partial cross-sectional view of a balloon catheter.

FIG. 16 is a partial cross-sectional view of the balloon catheter ofFIG. 15 in a deflated condition.

FIG. 17 is a partial cross-sectional view of a balloon catheter.

FIG. 18 is a partial cross-sectional view of the balloon catheter ofFIG. 17 in a deflated condition.

FIG. 19 is a partial cross-sectional view of a balloon catheter in afirst state.

FIG. 20 is a partial cross-sectional view of the balloon catheter ofFIG. 19 in a second state.

FIG. 21 is a partial cross-sectional view of a balloon catheter.

FIG. 22 is a cross-sectional view of the balloon catheter of FIG. 21.

FIG. 23 is a cross-sectional view of the balloon catheter of FIG. 21.

FIG. 24 is a partial cross-sectional view of a balloon catheter.

FIG. 25 is a cross-sectional view of the balloon catheter of FIG. 24.

FIG. 26 is a cross-sectional view of the balloon catheter of FIG. 24.

FIG. 27 is a partial cross-sectional view of a balloon catheter.

FIG. 28 is a perspective view of a catheter shaft.

FIG. 29 is a perspective view of a catheter shaft.

FIG. 30 is a perspective view of a spacer.

FIG. 31 is a cross-sectional view of a catheter shaft.

FIG. 32 is a perspective view of a spacer.

FIG. 33 is a cross-sectional view of a catheter shaft.

FIG. 34 is a partial cross-sectional view of a balloon catheter.

FIG. 35 is a cross-sectional view of the catheter shaft of FIG. 34.

FIG. 36 is a partial cross-sectional view of a balloon catheter.

FIG. 37 is a side view of a catheter shaft.

FIG. 38 is a partial perspective view of a catheter shaft.

FIG. 39 is a partial perspective view of a catheter shaft.

DETAILED DESCRIPTION

Reference is now made to the figures, in which like element numbersrefer to like elements throughout.

FIG. 1 is a partial diagrammatic side view of a balloon catheter havingan inner tubular member 2 defining a guidewire lumen and an outertubular member 14 defining an inflation lumen. A balloon 4 has aproximal waist 10 sealingly attached to the outer tubular member 14 anda distal waist 12 sealingly attached to the inner tubular member 12. Theballoon defines an inflation cavity and may include a proximal cone 6and a distal cone 8. The distal end of the outer tubular member may bespaced apart from the surface of the inner tubular member to permit theflow of inflation fluid therethrough. The opening formed by the outertubular member distal end and the inner tubular member is annular,although it may have other shapes. For example, a balloon catheter mayinclude a crescent-shaped opening. The distal end of the outer tubularmember may extend into the balloon cavity and there may be one or moreorifices 16 in the side wall of the outer tubular member. These orifices16 may provide additional pathways for inflation fluid. A stopper 20 isaffixed to the inner tubular member and is disposed in the ballooncavity. The stopper has an outer profile that prevents distal movementof the outer tubular member with respect to the inner tubular member butpermits distal movement of the inner tubular member with respect to theouter tubular member. The stopper may be located further from or closerto the distal end of the outer tubular member as desired. For example,the stopper may abut the distal end of the outer tubular member. Stopper20 includes several lobes 20 that define gaps therebetween that permitfluid flow to and from the distal end of the outer tubular member evenwhen the stopper abuts the distal end thereof.

FIG. 2 is a partial diagrammatic view of a balloon catheter having aninner tubular member 2, a balloon 4 defining a balloon cavity and anouter tubular member 14. Attached to the inner tubular member is abasket 22. The basket has a proximal end that prevents the outer tubularmember from moving distally relative to the inner tubular member butallows elongation of the balloon. The basket may include arms that canbe compressed against the inner tubular member and are biased to springout to the position shown. The basket may be made from metal, polymerresin or other suitable material. The outer tubular member may includeorifices 16 that allow for inflation and deflation of the balloon.

FIG. 3 is a partial diagrammatic view of a balloon catheter having aninner tubular member 2, a balloon 4 defining a balloon cavity and anouter tubular member 14. A stopper 24 is attached to the inner tubularmember. The stopper may flare proximally to abut against or envelop thedistal end of the outer tubular member and thus prevent the outertubular member from moving distally relative to the inner tubular memberwhile permitting balloon elongation. Orifices 16 may be included in theouter tubular member to provide a fluid flow path for inflation fluid.

FIG. 4 is a partial diagrammatic view of a balloon catheter having aninner tubular member 2, a balloon 4 defining a balloon cavity and anouter tubular member 14. A stopper 25 is attached to the inner tubularmember. The stopper is sized to abut against the distal end of the outertubular member and prevent distal movement thereof. The stopper mayinclude lumens extending from the proximal face to the distal face toprovide a fluid flow path for the inflation fluid. Alternatively or inaddition, orifices 16 may be provided in the distal end of the outertubular member.

FIG. 5 is a partial diagrammatic view of a balloon catheter having aninner tubular member 26, a balloon 4 defining a balloon cavity and anouter tubular member 14. Inner tubular member 26 has a first outerprofile and a second outer profile distal the first outer diameter andof greater size. The second outer profile is sized to prevent the distalpassage of the outer tubular member thereon. The two sections of theinner tubular member may be joined by a flare 28, a step-wise increase,or other suitable configuration. The outer tubular member may includeorifices 16 to provide an additional fluid flow path.

FIG. 6 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14. The proximal waist of balloon 4 extends distally ofthe distal end of outer tubular member 14. A stopper 30 is attached tothe inner tubular member and flares proximally to abut the distal end ofthe outer tubular member within the proximal balloon waist and preventrelative distal motion of the outer tubular member. As shown in FIG. 7,the stopper includes slots 32 to provide a fluid flow path. The stoppermay have different configurations. For example, the stopper may besubstantially cylindrical and have lumens extending longitudinallytherethrough to provide an inflation fluid flow path.

FIG. 8 is a partial diagrammatic view of a balloon catheter having aninner tubular member 2, a balloon 4 defining an inflation cavity and anouter tubular member 14. A slidable stopper 34 is disposed on the innertubular member. Stopper 34 is prevented from moving distally beyondradiopaque marker 36 by the proximal profile of the marker. The distalend of the outer tubular member is prevented from moving distally beyondthe stopper by the proximal profile of the stopper. Orifices 16 may beincluded to provide additional fluid flow paths.

FIG. 9 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14. A wire 38 disposed in the lumen of the outer tubularmember and attached proximally to a proximal part of the outer tubularmember and distal to the inner tubular member proximate the proximalwaist of the balloon reduces relative movement of the inner and outertubular members and may provide increased column strength. The term wireis used in this example embodiment and in all places in this applicationto denote a component having a length that is substantially greater thanthe transverse dimensions. The term wire does not imply a specificshape, cross-section or material. For example, a metal, a polymer resinor any suitable material may be used for wire 38. In an additionalexample, wire 38 could have a square, hollow, or variable cross-section.As shown in FIG. 10, the wire may have a coil 40. The coil is shown atthe distal end of the wire but may be located elsewhere, such as furtherproximally. The coil is proximal the distal connection of the wire tothe inner tubular member. The coil can compress along the longitudinalaxis of the catheter to prevent relative movement of the inner and outertubular members while permitting longitudinal expansion of the balloon.As shown in FIG. 11, wire 38 may have multiple distal attachment points42 or may extend to a radiopaque marker 36 as shown in FIG. 12. Wire 38may extend over only a portion of the catheter. For example, wire 38 maybe attached proximally to a midpoint of the outer tubular member anddistally to the inner tubular member at a radiopaque marker.

FIG. 13 is a partial diagrammatic view of a balloon catheter having aninner tubular member 2, a balloon 4 defining an inflation cavity and anouter tubular member 14. A closely wound coil 44 is disposed on theinner tubular member in the balloon cavity. The coil may be attached ata proximal end to the outer tubular member and at a distal end to thedistal waist of the balloon. The coil provides columnar support toprevent distal movement of the outer tubular member from compressing theballoon while permitting the balloon to expand. The coil may be a spiralcut tube, a shaped wire coil or other suitable configuration. In theembodiment depicted in FIG. 14, the coil is also distally attached tothe inner tubular member.

FIG. 15 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14 in an expanded position. FIG. 16 depicts the ballooncatheter in a contracted position. The balloon catheter includes texture46 on the inner surface of the balloon and texture 48 on the outersurface of the inner tubular member. When in the contracted position,textures 46 and 48 interact and mesh to prevent relative movement of theinner tubular member and the balloon. Textures 46 and 48 may be anycompatible textures. For example, texture 48 may be a plurality oftransverse or zigzag ribs and texture 46 may be small protrusions.Conversely, texture 46 may be transverse or zigzag ribs and texture 48may be protrusions or ribs. Any suitable texture may be used.

FIG. 17 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14 in an expanded position. FIG. 18 depicts the ballooncatheter in a contracted position. On the inner surface of the balloonand the outer surface of the inner tubular member in the balloon cavity,a tacky adhesive 50 is disposed. Adhesive 50 is tacky but not so strongas to prevent inflation of the balloon and operates to prevent relativelongitudinal motion between the balloon and the inner catheter. Adhesive50 may be, for example, an uncured rubber gum. In some embodiments,adhesive 50 may lose its adhesive qualities once the balloon has beeninflated. In some embodiments, adhesive 50 may be applied only to theballoon wall or only to the outer surface of the inner tubular member.

FIG. 19 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14. A stopper 52 is attached to both the inner tubularmember and the outer tubular member. The stopper includes severaltelescoping rings which collapse as shown in FIG. 20. Alternatively, thestopper includes a plurality of interlocking segments that slide intoeach other. The stopper permits only a limited range of relativemovement between the inner tubular member and the outer tubular member.

FIG. 20 is a partial side view of a balloon catheter having an innertubular member 54, a balloon 4 defining an inflation cavity and an outertubular member 56. As can be seen in FIG. 22, inner tubular member 54has a non-circular cross sectional profile. In this embodiment theprofile is hexagonal, but other suitable profiles include but are notlimited to pentagonal, gear-shaped, elliptical, and screw-shaped. Theouter surface of the inner tubular member contacts the inner surface ofthe outer tubular member proximate the proximal end of the balloon. Theinner catheter is in an interference fit with the outer catheter,preventing relative movement thereof. In other embodiments, adhesive orwelding may be used to join the inner and outer catheters. Thenon-circular profile of the inner catheter ensures that one or morelumens remain open for the passage of the inflation medium, as can beseen in FIG. 23. In other embodiments, the outer catheter may have anon-circular inner profile that creates an interference fit with asubstantially circular inner catheter. The outer catheter may have areduced distal profile to engage the inner catheter.

FIG. 24 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14. An insert 58 is disposed between the outer tubularmember and the inner tubular member and prevents relative longitudinalmovement between the two. The insert extends distally into the ballooncavity. Insert 58 may have an interference fit with one or both of theouter and inner tubular members or may be adhesively joined or welded toone or both of the outer and inner tubular members. Insert 58 has anon-circular outer profile as may be seen in FIG. 26. The profile ofinsert 58 is hexagonal, but many profiles are suitable, some of whichhave been described above. The profile of the insert provides lumens forthe passage of inflation fluid to the balloon. In other embodiments,insert 58 has a non-circular inner profile. Circular and non-circularare terms used with respect to the balloon catheters depicted herein. Acircular profile is a profile that may be coincident with the profile ofone of the tubular members, all of which are shown herein as circular.However, non-circular tubular members may be used and in such cases, theprofile of the insert may be modified to be used with the non-circulartubular member. In other words, the term circular is not intended to beso limiting.

FIG. 27 is a partial side view of a balloon catheter having an innertubular member 2, a balloon 4 defining an inflation cavity and an outertubular member 14. An insert 60 is disposed between the outer tubularmember and the inner tubular member and prevents relative longitudinalmovement between the two. The insert is positioned proximally of theouter tubular member distal end, although other positions may be suited.For example, the insert may be placed at the outer tubular member distalend. FIGS. 28 and 29 are perspective views depicting example tubularmembers disposed on inner tubular members 2. Both insert 60 and insert62 have circular inner and outer profiles and both have lumen patternstherethrough to provide a pathway for inflation fluid. FIG. 30 is aperspective view of an insert 64 having a noncircular hexagonal outerprofile. FIG. 31 depicts a cross-sectional view of a balloon catheterhaving this insert therein. FIG. 32 is a perspective view of an insert66 having a noncircular elliptical outer profile. FIG. 33 depicts across-sectional view of a balloon catheter having this insert therein.As can be readily inferred from these four example inserts, many insertswith varied profiles may be suitable.

FIG. 34 is a diagrammatic side view of a balloon catheter having aninner tubular member 2, a balloon 4 and an outer tubular member 14. Aprotrusion 68 is attached to the inner tubular member and is confined bya protrusion 70 attached to the outer tubular member. The inner cathetercan rotate with respect to the outer catheter at this point, but hasvery limited proximal or distal relative motion. As can be seen fromFIG. 35, protrusion 70 is a ring defining an annular groove. The ringmay have proximal and distal tapers as shown. Protrusion 68 includesfour tabs (though fewer or more tabs may be used) that are trapped inthe annular groove. The combination of the protrusions does not fullyocclude the inflation lumen, thereby providing the inflation fluid witha path to the balloon. Other embodiments may include variations of this.For example, one embodiment not pictured has a protrusion on the innertubular member that is a ring defining an annular groove and aprotrusion on the outer tubular member that has five tabs confined inthe groove. FIG. 36 depicts an embodiment having a ring 68 on the innertubular member confined by pairs of tabs 72 on the outer tubularmembers. Tabs 72 may or may not be axially aligned. FIG. 37 is aperspective view of an example outer tubular member 74. Protrusions maybe created in outer tubular member 74 by forming indents 76 in the outersurface of the member. Such indents may be thermoformed, for example.FIG. 38 depicts a balloon catheter having rounded protrusions 78 on theinner tubular member forming a channel for confining protrusions 80 onthe outer tubular member. Protrusions 80 are one, two or more beadsdisposed on the inner surface of the outer tubular member. FIG. 39depicts a balloon catheter having tapered protrusions 82 defining achannel for confining protrusions 84. Protrusions 84 may be one, two ormore tabs extending from the inner surface of the outer tubular member.

Numerous advantages of the invention covered by this document have beenset forth in the foregoing description. It will be understood, however,that this disclosure is, in many respects, only illustrative. Changesmay be made in details, particularly in matters of shape, size, andarrangement of parts without exceeding the scope of the invention. Noneof the description in the present application should be read as implyingthat any particular element, step, or function is an essential elementwhich must be included in the claim scope. Moreover, none of theseclaims are intended to invoke 35 U.S.C. .sctn. 112, 6 unless the exactwords “means for” are followed by a participle. The invention's scopeis, of course, defined in the language in which the appended claims areexpressed.

What is claimed is:
 1. A medical device, comprising: an expandablemember having a proximal waist and a distal waist; an outer memberhaving a proximal end, a distal end and a lumen extending therein,wherein the outer member is attached to the proximal waist of theexpandable member; an inner member having a proximal end and a distalend, the inner member disposed within the lumen of the outer member,wherein the inner member is attached to the distal waist of theexpandable member; and a movement limiting member connecting the innermember to the outer member, wherein the movement limiting member is acoil having a proximal end and a distal end, wherein the distal end ofthe coil is directly attached to the inner member; wherein the movementlimiting member is configured to limit movement of the outer memberrelative to the inner member.
 2. The medical device of claim 1, whereina portion of the inner member is positioned distal to the movementlimiting member, and wherein the portion of the inner member positioneddistal to the movement limiting member is configured to move distallywith respect to the outer member.
 3. The medical device of claim 1,wherein the distal end of outer member extends distally of the proximalwaist of the expandable member.
 4. The medical device of claim 3,wherein the distal end of the outer member extends into a cavity of theexpandable member.
 5. The medical device of claim 1, wherein themovement limiting member reduces relative movement of the inner andouter tubular members and provides increased column strength.
 6. Themedical device of claim 1, wherein the movement limiting member preventsdistal movement of the outer tubular member from compressing the balloonwhile permitting the balloon to expand.